<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>一元运算符</title>
</head>
<body>
        <script>
            var a = 99;
            var b = ++a;
            // a = 100
            // b = 100
            console.log(a);
            console.log(b)
        </script>
</body>
</html>